package com.youngdatafan.dataintegration.core.util.json;

import java.io.IOException;
import java.io.StringWriter;
import java.io.Writer;
import java.lang.reflect.Array;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.json.JSONException;
import org.json.JSONPointer;
import org.json.JSONPointerException;

/**
 * JSONArray.
 *
 * @author gavin
 * @since 2020/2/16 2:25 下午
 */
public class JSONArray implements Iterable<Object> {

    /**
     * The arrayList where the JSONArray's properties are kept.
     */
    private final ArrayList<Object> myArrayList;

    /**
     * Construct an empty JSONArray.
     */
    public JSONArray() {
        this.myArrayList = new ArrayList<>();
    }

    /**
     * Construct a JSONArray from a JSONLinkedTokener.
     *
     * @param x A JSONLinkedTokener
     * @throws JSONException If there is a syntax error.
     */
    public JSONArray(JSONLinkedTokener x) throws JSONException {
        this();
        if (x.nextClean() != '[') {
            throw x.syntaxError("A JSONArray text must start with '['");
        }

        char nextChar = x.nextClean();
        if (nextChar == 0) {
            // array is unclosed. No ']' found, instead EOF
            throw x.syntaxError("Expected a ',' or ']'");
        }
        if (nextChar != ']') {
            x.back();
            for (; ; ) {
                if (x.nextClean() == ',') {
                    x.back();
                    this.myArrayList.add(JSONLinkedObject.NULL);
                } else {
                    x.back();
                    this.myArrayList.add(x.nextValue());
                }
                switch (x.nextClean()) {
                    case 0:
                        // array is unclosed. No ']' found, instead EOF
                        throw x.syntaxError("Expected a ',' or ']'");
                    case ',':
                        nextChar = x.nextClean();
                        if (nextChar == 0) {
                            // array is unclosed. No ']' found, instead EOF
                            throw x.syntaxError("Expected a ',' or ']'");
                        }
                        if (nextChar == ']') {
                            return;
                        }
                        x.back();
                        break;
                    case ']':
                        return;
                    default:
                        throw x.syntaxError("Expected a ',' or ']'");
                }
            }
        }
    }

    /**
     * Construct a JSONArray from a source JSON text.
     *
     * @param source A string that begins with <code>[</code>&nbsp;<small>(left
     *               bracket)</small> and ends with <code>]</code>
     *               &nbsp;<small>(right bracket)</small>.
     * @throws JSONException If there is a syntax error.
     */
    public JSONArray(String source) throws JSONException {
        this(new JSONLinkedTokener(source));
    }

    /**
     * Construct a JSONArray from a Collection.
     *
     * @param collection A Collection.
     */
    public JSONArray(Collection<?> collection) {
        if (collection == null) {
            this.myArrayList = new ArrayList<Object>();
        } else {
            this.myArrayList = new ArrayList<Object>(collection.size());
            for (Object o : collection) {
                this.myArrayList.add(JSONLinkedObject.wrap(o));
            }
        }
    }

    /**
     * Construct a JSONArray from an array.
     *
     * @throws JSONException If not an array or if an array value is non-finite number.
     */
    public JSONArray(Object array) throws JSONException {
        this();
        if (array.getClass().isArray()) {
            int length = Array.getLength(array);
            this.myArrayList.ensureCapacity(length);
            for (int i = 0; i < length; i += 1) {
                this.put(JSONLinkedObject.wrap(Array.get(array, i)));
            }
        } else {
            throw new JSONException(
                "JSONArray initial value should be a string or collection or array.");
        }
    }

    @Override
    public Iterator<Object> iterator() {
        return this.myArrayList.iterator();
    }

    /**
     * Get the object value associated with an index.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return An object value.
     * @throws JSONException If there is no value for the index.
     */
    public Object get(int index) throws JSONException {
        Object object = this.opt(index);
        if (object == null) {
            throw new JSONException("JSONArray[" + index + "] not found.");
        }
        return object;
    }

    /**
     * Get the boolean value associated with an index. The string values "true"
     * and "false" are converted to boolean.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return The truth.
     * @throws JSONException If there is no value for the index or if the value is not
     *                       convertible to boolean.
     */
    public boolean getBoolean(int index) throws JSONException {
        Object object = this.get(index);
        if (object.equals(Boolean.FALSE)
            || (object instanceof String && "false".equalsIgnoreCase((String) object))) {
            return false;
        } else if (object.equals(Boolean.TRUE)
            || (object instanceof String && "true".equalsIgnoreCase((String) object))) {
            return true;
        }
        throw new JSONException("JSONArray[" + index + "] is not a boolean.");
    }

    /**
     * Get the double value associated with an index.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return The value.
     * @throws JSONException If the key is not found or if the value cannot be converted
     *                       to a number.
     */
    public double getDouble(int index) throws JSONException {
        Object object = this.get(index);
        try {
            return object instanceof Number ? ((Number) object).doubleValue()
                : Double.parseDouble((String) object);
        } catch (Exception e) {
            throw new JSONException("JSONArray[" + index + "] is not a number.", e);
        }
    }

    /**
     * Get the float value associated with a key.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return The numeric value.
     * @throws JSONException if the key is not found or if the value is not a Number
     *                       object and cannot be converted to a number.
     */
    public float getFloat(int index) throws JSONException {
        Object object = this.get(index);
        try {
            return object instanceof Number ? ((Number) object).floatValue()
                : Float.parseFloat(object.toString());
        } catch (Exception e) {
            throw new JSONException("JSONArray[" + index
                + "] is not a number.", e);
        }
    }

    /**
     * Get the Number value associated with a key.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return The numeric value.
     * @throws JSONException if the key is not found or if the value is not a Number
     *                       object and cannot be converted to a number.
     */
    public Number getNumber(int index) throws JSONException {
        Object object = this.get(index);
        try {
            if (object instanceof Number) {
                return (Number) object;
            }
            return JSONLinkedObject.stringToNumber(object.toString());
        } catch (Exception e) {
            throw new JSONException("JSONArray[" + index + "] is not a number.", e);
        }
    }

    /**
     * Get the enum value associated with an index.
     *
     * @param clazz The type of enum to retrieve.
     * @param index The index must be between 0 and length() - 1.
     * @param <E>   Enum
     * @return The enum value at the index location
     * @throws JSONException if the key is not found or if the value cannot be converted
     *                       to an enum.
     */
    public <E extends Enum<E>> E getEnum(Class<E> clazz, int index) throws JSONException {
        E val = optEnum(clazz, index);
        if (val == null) {
            // JSONException should really take a throwable argument.
            // If it did, I would re-implement this with the Enum.valueOf
            // method and place any thrown exception in the JSONException
            throw new JSONException("JSONArray[" + index + "] is not an enum of type "
                + JSONLinkedObject.quote(clazz.getSimpleName()) + ".");
        }
        return val;
    }

    /**
     * Get the BigDecimal value associated with an index.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return The value.
     * @throws JSONException If the key is not found or if the value cannot be converted
     *                       to a BigDecimal.
     */
    public BigDecimal getBigDecimal(int index) throws JSONException {
        Object object = this.get(index);
        try {
            return new BigDecimal(object.toString());
        } catch (Exception e) {
            throw new JSONException("JSONArray[" + index + "] could not convert to BigDecimal.", e);
        }
    }

    /**
     * Get the BigInteger value associated with an index.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return The value.
     * @throws JSONException If the key is not found or if the value cannot be converted
     *                       to a BigInteger.
     */
    public BigInteger getBigInteger(int index) throws JSONException {
        Object object = this.get(index);
        try {
            return new BigInteger(object.toString());
        } catch (Exception e) {
            throw new JSONException("JSONArray[" + index + "] could not convert to BigInteger.", e);
        }
    }

    /**
     * Get the int value associated with an index.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return The value.
     * @throws JSONException If the key is not found or if the value is not a number.
     */
    public int getInt(int index) throws JSONException {
        Object object = this.get(index);
        try {
            return object instanceof Number ? ((Number) object).intValue()
                : Integer.parseInt((String) object);
        } catch (Exception e) {
            throw new JSONException("JSONArray[" + index + "] is not a number.", e);
        }
    }

    /**
     * Get the JSONArray associated with an index.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return A JSONArray value.
     * @throws JSONException If there is no value for the index. or if the value is not a
     *                       JSONArray
     */
    public JSONArray getJSONArray(int index) throws JSONException {
        Object object = this.get(index);
        if (object instanceof JSONArray) {
            return (JSONArray) object;
        }
        throw new JSONException("JSONArray[" + index + "] is not a JSONArray.");
    }

    /**
     * Get the JSONLinkedObject associated with an index.
     *
     * @param index subscript
     * @return A JSONLinkedObject value.
     * @throws JSONException If there is no value for the index or if the value is not a
     *                       JSONLinkedObject
     */
    public JSONLinkedObject getJSONLinkedObject(int index) throws JSONException {
        Object object = this.get(index);
        if (object instanceof JSONLinkedObject) {
            return (JSONLinkedObject) object;
        }
        throw new JSONException("JSONArray[" + index + "] is not a JSONLinkedObject.");
    }

    /**
     * Get the long value associated with an index.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return The value.
     * @throws JSONException If the key is not found or if the value cannot be converted
     *                       to a number.
     */
    public long getLong(int index) throws JSONException {
        Object object = this.get(index);
        try {
            return object instanceof Number ? ((Number) object).longValue()
                : Long.parseLong((String) object);
        } catch (Exception e) {
            throw new JSONException("JSONArray[" + index + "] is not a number.", e);
        }
    }

    /**
     * Get the string associated with an index.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return A string value.
     * @throws JSONException If there is no string value for the index.
     */
    public String getString(int index) throws JSONException {
        Object object = this.get(index);
        if (object instanceof String) {
            return (String) object;
        }
        throw new JSONException("JSONArray[" + index + "] not a string.");
    }

    /**
     * Determine if the value is <code>null</code>.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return true if the value at the index is <code>null</code>, or if there is no value.
     */
    public boolean isNull(int index) {
        return JSONLinkedObject.NULL.equals(this.opt(index));
    }

    /**
     * Make a string from the contents of this JSONArray. The
     * <code>separator</code> string is inserted between each element. Warning:
     * This method assumes that the data structure is acyclical.
     *
     * @param separator A string that will be inserted between the elements.
     * @return a string.
     * @throws JSONException If the array contains an invalid number.
     */
    public String join(String separator) throws JSONException {
        int len = this.length();
        StringBuilder sb = new StringBuilder();

        for (int i = 0; i < len; i += 1) {
            if (i > 0) {
                sb.append(separator);
            }
            sb.append(JSONLinkedObject.valueToString(this.myArrayList.get(i)));
        }
        return sb.toString();
    }

    /**
     * Get the number of elements in the JSONArray, included nulls.
     *
     * @return The length (or size).
     */
    public int length() {
        return this.myArrayList.size();
    }

    /**
     * Get the optional object value associated with an index.
     *
     * @param index The index must be between 0 and length() - 1. If not, null is returned.
     * @return An object value, or null if there is no object at that index.
     */
    public Object opt(int index) {
        return (index < 0 || index >= this.length()) ? null : this.myArrayList
            .get(index);
    }

    /**
     * Get the optional boolean value associated with an index. It returns false
     * if there is no value at that index, or if the value is not Boolean.TRUE
     * or the String "true".
     *
     * @param index The index must be between 0 and length() - 1.
     * @return The truth.
     */
    public boolean optBoolean(int index) {
        return this.optBoolean(index, false);
    }

    /**
     * Get the optional boolean value associated with an index. It returns the
     * defaultValue if there is no value at that index or if it is not a Boolean
     * or the String "true" or "false" (case insensitive).
     *
     * @param index        The index must be between 0 and length() - 1.
     * @param defaultValue A boolean default.
     * @return The truth.
     */
    public boolean optBoolean(int index, boolean defaultValue) {
        try {
            return this.getBoolean(index);
        } catch (Exception e) {
            return defaultValue;
        }
    }

    /**
     * Get the optional double value associated with an index. NaN is returned
     * if there is no value for the index, or if the value is not a number and
     * cannot be converted to a number.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return The value.
     */
    public double optDouble(int index) {
        return this.optDouble(index, Double.NaN);
    }

    /**
     * Get the optional double value associated with an index. The defaultValue
     * is returned if there is no value for the index, or if the value is not a
     * number and cannot be converted to a number.
     *
     * @param index        subscript
     * @param defaultValue The default value.
     * @return The value.
     */
    public double optDouble(int index, double defaultValue) {
        Object val = this.opt(index);
        if (JSONLinkedObject.NULL.equals(val)) {
            return defaultValue;
        }
        if (val instanceof Number) {
            return ((Number) val).doubleValue();
        }
        if (val instanceof String) {
            try {
                return Double.parseDouble((String) val);
            } catch (Exception e) {
                return defaultValue;
            }
        }
        return defaultValue;
    }

    /**
     * Get the optional float value associated with an index. NaN is returned
     * if there is no value for the index, or if the value is not a number and
     * cannot be converted to a number.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return The value.
     */
    public float optFloat(int index) {
        return this.optFloat(index, Float.NaN);
    }

    /**
     * Get the optional float value associated with an index. The defaultValue
     * is returned if there is no value for the index, or if the value is not a
     * number and cannot be converted to a number.
     *
     * @param index        subscript
     * @param defaultValue The default value.
     * @return The value.
     */
    public float optFloat(int index, float defaultValue) {
        Object val = this.opt(index);
        if (JSONLinkedObject.NULL.equals(val)) {
            return defaultValue;
        }
        if (val instanceof Number) {
            return ((Number) val).floatValue();
        }
        if (val instanceof String) {
            try {
                return Float.parseFloat((String) val);
            } catch (Exception e) {
                return defaultValue;
            }
        }
        return defaultValue;
    }

    /**
     * Get the optional int value associated with an index. Zero is returned if
     * there is no value for the index, or if the value is not a number and
     * cannot be converted to a number.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return The value.
     */
    public int optInt(int index) {
        return this.optInt(index, 0);
    }

    /**
     * Get the optional int value associated with an index. The defaultValue is
     * returned if there is no value for the index, or if the value is not a
     * number and cannot be converted to a number.
     *
     * @param index        The index must be between 0 and length() - 1.
     * @param defaultValue The default value.
     * @return The value.
     */
    public int optInt(int index, int defaultValue) {
        Object val = this.opt(index);
        if (JSONLinkedObject.NULL.equals(val)) {
            return defaultValue;
        }
        if (val instanceof Number) {
            return ((Number) val).intValue();
        }

        if (val instanceof String) {
            try {
                return new BigDecimal(val.toString()).intValue();
            } catch (Exception e) {
                return defaultValue;
            }
        }
        return defaultValue;
    }

    /**
     * Get the enum value associated with a key.
     *
     * @param clazz The type of enum to retrieve.
     * @param index The index must be between 0 and length() - 1.
     * @param <E>   Enum
     * @return The enum value at the index location or null if not found
     */
    public <E extends Enum<E>> E optEnum(Class<E> clazz, int index) {
        return this.optEnum(clazz, index, null);
    }

    /**
     * Get the enum value associated with a key.
     *
     * @param clazz        The type of enum to retrieve.
     * @param index        The index must be between 0 and length() - 1.
     * @param defaultValue The default in case the value is not found
     * @param <E>          Enum
     * @return The enum value at the index location or defaultValue if the value is not found or cannot be assigned to clazz
     */
    public <E extends Enum<E>> E optEnum(Class<E> clazz, int index, E defaultValue) {
        try {
            Object val = this.opt(index);
            if (JSONLinkedObject.NULL.equals(val)) {
                return defaultValue;
            }
            if (clazz.isAssignableFrom(val.getClass())) {
                // we just checked it!
                @SuppressWarnings("unchecked")
                E myE = (E) val;
                return myE;
            }
            return Enum.valueOf(clazz, val.toString());
        } catch (IllegalArgumentException e) {
            return defaultValue;
        } catch (NullPointerException e) {
            return defaultValue;
        }
    }


    /**
     * Get the optional BigInteger value associated with an index. The
     * defaultValue is returned if there is no value for the index, or if the
     * value is not a number and cannot be converted to a number.
     *
     * @param index        The index must be between 0 and length() - 1.
     * @param defaultValue The default value.
     * @return The value.
     */
    public BigInteger optBigInteger(int index, BigInteger defaultValue) {
        Object val = this.opt(index);
        if (JSONLinkedObject.NULL.equals(val)) {
            return defaultValue;
        }
        if (val instanceof BigInteger) {
            return (BigInteger) val;
        }
        if (val instanceof BigDecimal) {
            return ((BigDecimal) val).toBigInteger();
        }
        if (val instanceof Double || val instanceof Float) {
            return new BigDecimal(((Number) val).doubleValue()).toBigInteger();
        }
        if (val instanceof Long || val instanceof Integer
            || val instanceof Short || val instanceof Byte) {
            return BigInteger.valueOf(((Number) val).longValue());
        }
        try {
            final String valStr = val.toString();
            if (JSONLinkedObject.isDecimalNotation(valStr)) {
                return new BigDecimal(valStr).toBigInteger();
            }
            return new BigInteger(valStr);
        } catch (Exception e) {
            return defaultValue;
        }
    }

    /**
     * Get the optional BigDecimal value associated with an index. The
     * defaultValue is returned if there is no value for the index, or if the
     * value is not a number and cannot be converted to a number.
     *
     * @param index        The index must be between 0 and length() - 1.
     * @param defaultValue The default value.
     * @return The value.
     */
    public BigDecimal optBigDecimal(int index, BigDecimal defaultValue) {
        Object val = this.opt(index);
        if (JSONLinkedObject.NULL.equals(val)) {
            return defaultValue;
        }
        if (val instanceof BigDecimal) {
            return (BigDecimal) val;
        }
        if (val instanceof BigInteger) {
            return new BigDecimal((BigInteger) val);
        }
        if (val instanceof Double || val instanceof Float) {
            return new BigDecimal(((Number) val).doubleValue());
        }
        if (val instanceof Long || val instanceof Integer
            || val instanceof Short || val instanceof Byte) {
            return new BigDecimal(((Number) val).longValue());
        }
        try {
            return new BigDecimal(val.toString());
        } catch (Exception e) {
            return defaultValue;
        }
    }

    /**
     * Get the optional JSONArray associated with an index.
     *
     * @param index subscript
     * @return A JSONArray value, or null if the index has no value, or if the value is not a JSONArray.
     */
    public JSONArray optJSONArray(int index) {
        Object o = this.opt(index);
        return o instanceof JSONArray ? (JSONArray) o : null;
    }

    /**
     * Get the optional JSONLinkedObject associated with an index. Null is returned if
     * the key is not found, or null if the index has no value, or if the value
     * is not a JSONLinkedObject.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return A JSONLinkedObject value.
     */
    public JSONLinkedObject optJSONLinkedObject(int index) {
        Object o = this.opt(index);
        return o instanceof JSONLinkedObject ? (JSONLinkedObject) o : null;
    }

    /**
     * Get the optional long value associated with an index. Zero is returned if
     * there is no value for the index, or if the value is not a number and
     * cannot be converted to a number.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return The value.
     */
    public long optLong(int index) {
        return this.optLong(index, 0);
    }

    /**
     * Get the optional long value associated with an index. The defaultValue is
     * returned if there is no value for the index, or if the value is not a
     * number and cannot be converted to a number.
     *
     * @param index        The index must be between 0 and length() - 1.
     * @param defaultValue The default value.
     * @return The value.
     */
    public long optLong(int index, long defaultValue) {
        Object val = this.opt(index);
        if (JSONLinkedObject.NULL.equals(val)) {
            return defaultValue;
        }
        if (val instanceof Number) {
            return ((Number) val).longValue();
        }

        if (val instanceof String) {
            try {
                return new BigDecimal(val.toString()).longValue();
            } catch (Exception e) {
                return defaultValue;
            }
        }
        return defaultValue;
    }

    /**
     * Get an optional {@link Number} value associated with a key, or <code>null</code>
     * if there is no such key or if the value is not a number. If the value is a string,
     * an attempt will be made to evaluate it as a number ({@link BigDecimal}). This method
     * would be used in cases where type coercion of the number value is unwanted.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return An object which is the value.
     */
    public Number optNumber(int index) {
        return this.optNumber(index, null);
    }

    /**
     * Get an optional {@link Number} value associated with a key, or the default if there
     * is no such key or if the value is not a number. If the value is a string,
     * an attempt will be made to evaluate it as a number ({@link BigDecimal}). This method
     * would be used in cases where type coercion of the number value is unwanted.
     *
     * @param index        The index must be between 0 and length() - 1.
     * @param defaultValue The default.
     * @return An object which is the value.
     */
    public Number optNumber(int index, Number defaultValue) {
        Object val = this.opt(index);
        if (JSONLinkedObject.NULL.equals(val)) {
            return defaultValue;
        }
        if (val instanceof Number) {
            return (Number) val;
        }

        if (val instanceof String) {
            try {
                return JSONLinkedObject.stringToNumber((String) val);
            } catch (Exception e) {
                return defaultValue;
            }
        }
        return defaultValue;
    }

    /**
     * Get the optional string value associated with an index. It returns an
     * empty string if there is no value at that index. If the value is not a
     * string and is not null, then it is converted to a string.
     *
     * @param index The index must be between 0 and length() - 1.
     * @return A String value.
     */
    public String optString(int index) {
        return this.optString(index, "");
    }

    /**
     * Get the optional string associated with an index. The defaultValue is
     * returned if the key is not found.
     *
     * @param index        The index must be between 0 and length() - 1.
     * @param defaultValue The default value.
     * @return A String value.
     */
    public String optString(int index, String defaultValue) {
        Object object = this.opt(index);
        return JSONLinkedObject.NULL.equals(object) ? defaultValue : object
            .toString();
    }

    /**
     * Append a boolean value. This increases the array's length by one.
     *
     * @param value A boolean value.
     * @return this.
     */
    public JSONArray put(boolean value) {
        return this.put(value ? Boolean.TRUE : Boolean.FALSE);
    }

    /**
     * Put a value in the JSONArray, where the value will be a JSONArray which
     * is produced from a Collection.
     *
     * @param value A Collection value.
     * @return this.
     */
    public JSONArray put(Collection<?> value) {
        return this.put(new JSONArray(value));
    }

    /**
     * Append a double value. This increases the array's length by one.
     *
     * @param value A double value.
     * @return this.
     * @throws JSONException if the value is not finite.
     */
    public JSONArray put(double value) throws JSONException {
        return this.put(Double.valueOf(value));
    }

    /**
     * Append a float value. This increases the array's length by one.
     *
     * @param value A float value.
     * @return this.
     * @throws JSONException if the value is not finite.
     */
    public JSONArray put(float value) throws JSONException {
        return this.put(Float.valueOf(value));
    }

    /**
     * Append an int value. This increases the array's length by one.
     *
     * @param value An int value.
     * @return this.
     */
    public JSONArray put(int value) {
        return this.put(Integer.valueOf(value));
    }

    /**
     * Append an long value. This increases the array's length by one.
     *
     * @param value A long value.
     * @return this.
     */
    public JSONArray put(long value) {
        return this.put(Long.valueOf(value));
    }

    /**
     * Put a value in the JSONArray, where the value will be a JSONLinkedObject which
     * is produced from a Map.
     *
     * @param value A Map value.
     * @return this.
     * @throws NullPointerException If a key in the map is <code>null</code>
     */
    public JSONArray put(Map<?, ?> value) {
        return this.put(new JSONLinkedObject(value));
    }

    /**
     * Append an object value. This increases the array's length by one.
     *
     * @param value An object value. The value should be a Boolean, Double,
     *              Integer, JSONArray, JSONLinkedObject, Long, or String, or the
     *              JSONLinkedObject.NULL object.
     * @return this.
     */
    public JSONArray put(Object value) {
        JSONLinkedObject.testValidity(value);
        this.myArrayList.add(value);
        return this;
    }

    /**
     * Put or replace a boolean value in the JSONArray. If the index is greater
     * than the length of the JSONArray, then null elements will be added as
     * necessary to pad it out.
     *
     * @param index The subscript.
     * @param value A boolean value.
     * @return this.
     * @throws JSONException If the index is negative.
     */
    public JSONArray put(int index, boolean value) throws JSONException {
        return this.put(index, value ? Boolean.TRUE : Boolean.FALSE);
    }

    /**
     * Put a value in the JSONArray, where the value will be a JSONArray which
     * is produced from a Collection.
     *
     * @param index The subscript.
     * @param value A Collection value.
     * @return this.
     * @throws JSONException If the index is negative or if the value is non-finite.
     */
    public JSONArray put(int index, Collection<?> value) throws JSONException {
        return this.put(index, new JSONArray(value));
    }

    /**
     * Put or replace a double value. If the index is greater than the length of
     * the JSONArray, then null elements will be added as necessary to pad it
     * out.
     *
     * @param index The subscript.
     * @param value A double value.
     * @return this.
     * @throws JSONException If the index is negative or if the value is non-finite.
     */
    public JSONArray put(int index, double value) throws JSONException {
        return this.put(index, Double.valueOf(value));
    }

    /**
     * Put or replace a float value. If the index is greater than the length of
     * the JSONArray, then null elements will be added as necessary to pad it
     * out.
     *
     * @param index The subscript.
     * @param value A float value.
     * @return this.
     * @throws JSONException If the index is negative or if the value is non-finite.
     */
    public JSONArray put(int index, float value) throws JSONException {
        return this.put(index, Float.valueOf(value));
    }

    /**
     * Put or replace an int value. If the index is greater than the length of
     * the JSONArray, then null elements will be added as necessary to pad it
     * out.
     *
     * @param index The subscript.
     * @param value An int value.
     * @return this.
     * @throws JSONException If the index is negative.
     */
    public JSONArray put(int index, int value) throws JSONException {
        return this.put(index, Integer.valueOf(value));
    }

    /**
     * Put or replace a long value. If the index is greater than the length of
     * the JSONArray, then null elements will be added as necessary to pad it
     * out.
     *
     * @param index The subscript.
     * @param value A long value.
     * @return this.
     * @throws JSONException If the index is negative.
     */
    public JSONArray put(int index, long value) throws JSONException {
        return this.put(index, Long.valueOf(value));
    }

    /**
     * Put a value in the JSONArray, where the value will be a JSONLinkedObject that
     * is produced from a Map.
     *
     * @param index The subscript.
     * @param value The Map value.
     * @return this.
     * @throws JSONException If the index is negative or if the the value is an invalid
     *                       number.
     */
    public JSONArray put(int index, Map<?, ?> value) throws JSONException {
        this.put(index, new JSONLinkedObject(value));
        return this;
    }

    /**
     * Put or replace an object value in the JSONArray. If the index is greater
     * than the length of the JSONArray, then null elements will be added as
     * necessary to pad it out.
     *
     * @param index The subscript.
     * @param value The value to put into the array. The value should be a
     *              Boolean, Double, Integer, JSONArray, JSONLinkedObject, Long, or
     *              String, or the JSONLinkedObject.NULL object.
     * @return this.
     * @throws JSONException If the index is negative or if the the value is an invalid
     *                       number.
     */
    public JSONArray put(int index, Object value) throws JSONException {
        if (index < 0) {
            throw new JSONException("JSONArray[" + index + "] not found.");
        }
        if (index < this.length()) {
            JSONLinkedObject.testValidity(value);
            this.myArrayList.set(index, value);
            return this;
        }
        if (index == this.length()) {
            // simple append
            return this.put(value);
        }
        // if we are inserting past the length, we want to grow the array all at once
        // instead of incrementally.
        this.myArrayList.ensureCapacity(index + 1);
        while (index != this.length()) {
            // we don't need to test validity of NULL objects
            this.myArrayList.add(JSONLinkedObject.NULL);
        }
        return this.put(value);
    }

    /**
     * Creates a JSONPointer using an initialization string and tries to
     * match it to an item within this JSONArray. For example, given a
     * JSONArray initialized with this document:
     * <pre>
     * [
     *     {"b":"c"}
     * ]
     * </pre>
     * and this JSONPointer string:
     * <pre>
     * "/0/b"
     * </pre>
     * Then this method will return the String "c"
     * A JSONPointerException may be thrown from code called by this method.
     *
     * @param jsonPointer string that can be used to create a JSONPointer
     * @return the item matched by the JSONPointer, otherwise null
     */
    public Object query(String jsonPointer) {
        return query(new JSONPointer(jsonPointer));
    }

    /**
     * Uses a uaer initialized JSONPointer  and tries to
     * match it to an item whithin this JSONArray. For example, given a
     * JSONArray initialized with this document:
     * <pre>
     * [
     *     {"b":"c"}
     * ]
     * </pre>
     * and this JSONPointer:
     * <pre>
     * "/0/b"
     * </pre>
     * Then this method will return the String "c"
     * A JSONPointerException may be thrown from code called by this method.
     *
     * @param jsonPointer string that can be used to create a JSONPointer
     * @return the item matched by the JSONPointer, otherwise null
     */
    public Object query(JSONPointer jsonPointer) {
        return jsonPointer.queryFrom(this);
    }

    /**
     * Queries and returns a value from this object using {@code jsonPointer}, or
     * returns null if the query fails due to a missing key.
     *
     * @param jsonPointer the string representation of the JSON pointer
     * @return the queried value or {@code null}
     * @throws IllegalArgumentException if {@code jsonPointer} has invalid syntax
     */
    public Object optQuery(String jsonPointer) {
        return optQuery(new JSONPointer(jsonPointer));
    }

    /**
     * Queries and returns a value from this object using {@code jsonPointer}, or
     * returns null if the query fails due to a missing key.
     *
     * @param jsonPointer The JSON pointer
     * @return the queried value or {@code null}
     * @throws IllegalArgumentException if {@code jsonPointer} has invalid syntax
     */
    public Object optQuery(JSONPointer jsonPointer) {
        try {
            return jsonPointer.queryFrom(this);
        } catch (JSONPointerException e) {
            return null;
        }
    }

    /**
     * Remove an index and close the hole.
     *
     * @param index The index of the element to be removed.
     * @return The value that was associated with the index, or null if there was no value.
     */
    public Object remove(int index) {
        return index >= 0 && index < this.length() ? this.myArrayList.remove(index) : null;
    }

    /**
     * Determine if two JSONArrays are similar.
     * They must contain similar sequences.
     *
     * @param other The other JSONArray
     * @return true if they are equal
     */
    public boolean similar(Object other) {
        if (!(other instanceof JSONArray)) {
            return false;
        }
        int len = this.length();
        if (len != ((JSONArray) other).length()) {
            return false;
        }
        for (int i = 0; i < len; i += 1) {
            Object valueThis = this.myArrayList.get(i);
            Object valueOther = ((JSONArray) other).myArrayList.get(i);
            if (valueThis == valueOther) {
                continue;
            }
            if (valueThis == null) {
                return false;
            }
            if (valueThis instanceof JSONLinkedObject) {
                if (!((JSONLinkedObject) valueThis).similar(valueOther)) {
                    return false;
                }
            } else if (valueThis instanceof JSONArray) {
                if (!((JSONArray) valueThis).similar(valueOther)) {
                    return false;
                }
            } else if (!valueThis.equals(valueOther)) {
                return false;
            }
        }
        return true;
    }

    /**
     * Produce a JSONLinkedObject by combining a JSONArray of names with the values of
     * this JSONArray.
     *
     * @param names A JSONArray containing a list of key strings. These will be
     *              paired with the values.
     * @return A JSONLinkedObject, or null if there are no names or if this JSONArray has no values.
     * @throws JSONException If any of the names are null.
     */
    public JSONLinkedObject toJSONLinkedObject(JSONArray names) throws JSONException {
        if (names == null || names.isEmpty() || this.isEmpty()) {
            return null;
        }
        JSONLinkedObject jo = new JSONLinkedObject(names.length());
        for (int i = 0; i < names.length(); i += 1) {
            jo.put(names.getString(i), this.opt(i));
        }
        return jo;
    }

    /**
     * Make a JSON text of this JSONArray. For compactness, no unnecessary
     * whitespace is added. If it is not possible to produce a syntactically
     * correct JSON text then null will be returned instead. This could occur if
     * the array contains an invalid number.
     * Warning: This method assumes that the data structure is acyclical.
     *
     * @return a printable, displayable, transmittable representation of the array.
     */
    @Override
    public String toString() {
        try {
            return this.toString(0);
        } catch (Exception e) {
            return null;
        }
    }

    /**
     * Make a pretty-printed JSON text of this JSONArray.
     *
     * <p>If <code>indentFactor > 0</code> and the {@link JSONArray} has only
     * one element, then the array will be output on a single line:
     * <pre>{@code [1]}</pre>
     *
     * <p>If an array has 2 or more elements, then it will be output across
     * multiple lines: <pre>{@code
     * [
     * 1,
     * "value 2",
     * 3
     * ]
     * }</pre>
     * Warning: This method assumes that the data structure is acyclical.
     *
     * @param indentFactor The number of spaces to add to each level of indentation.
     * @return a printable, displayable, transmittable representation of the object, beginning with <code>[</code>&nbsp;<small>(left
     * bracket)</small> and ending with <code>]</code> &nbsp;<small>(right bracket)</small>.
     * @throws JSONException e
     */
    public String toString(int indentFactor) throws JSONException {
        StringWriter sw = new StringWriter();
        synchronized (sw.getBuffer()) {
            return this.write(sw, indentFactor, 0).toString();
        }
    }

    /**
     * Write the contents of the JSONArray as JSON text to a writer. For
     * compactness, no whitespace is added.
     * Warning: This method assumes that the data structure is acyclical.
     *
     * @param writer Writer
     * @return The writer.
     * @throws JSONException e
     */
    public Writer write(Writer writer) throws JSONException {
        return this.write(writer, 0, 0);
    }

    /**
     * Write the contents of the JSONArray as JSON text to a writer.
     *
     * <p>If <code>indentFactor > 0</code> and the {@link JSONArray} has only
     * one element, then the array will be output on a single line:
     * <pre>{@code [1]}</pre>
     *
     * <p>If an array has 2 or more elements, then it will be output across
     * multiple lines: <pre>{@code
     * [
     * 1,
     * "value 2",
     * 3
     * ]
     * }</pre>
     * Warning: This method assumes that the data structure is acyclical.
     *
     * @param writer       Writes the serialized JSON
     * @param indentFactor The number of spaces to add to each level of indentation.
     * @param indent       The indentation of the top level.
     * @return The writer.
     * @throws JSONException e
     */
    public Writer write(Writer writer, int indentFactor, int indent) throws JSONException {
        try {
            boolean commanate = false;
            int length = this.length();
            writer.write('[');

            if (length == 1) {
                try {
                    JSONLinkedObject.writeValue(writer, this.myArrayList.get(0),
                        indentFactor, indent);
                } catch (Exception e) {
                    throw new JSONException("Unable to write JSONArray value at index: 0", e);
                }
            } else if (length != 0) {
                final int newindent = indent + indentFactor;

                for (int i = 0; i < length; i += 1) {
                    if (commanate) {
                        writer.write(',');
                    }
                    if (indentFactor > 0) {
                        writer.write('\n');
                    }
                    JSONLinkedObject.indent(writer, newindent);
                    try {
                        JSONLinkedObject.writeValue(writer, this.myArrayList.get(i),
                            indentFactor, newindent);
                    } catch (Exception e) {
                        throw new JSONException("Unable to write JSONArray value at index: " + i, e);
                    }
                    commanate = true;
                }
                if (indentFactor > 0) {
                    writer.write('\n');
                }
                JSONLinkedObject.indent(writer, indent);
            }
            writer.write(']');
            return writer;
        } catch (IOException e) {
            throw new JSONException(e);
        }
    }

    /**
     * Returns a java.util.List containing all of the elements in this array.
     * If an element in the array is a JSONArray or JSONLinkedObject it will also
     * be converted.
     * Warning: This method assumes that the data structure is acyclical.
     *
     * @return a java.util.List containing the elements of this array
     */
    public List<Object> toList() {
        List<Object> results = new ArrayList<>(this.myArrayList.size());
        for (Object element : this.myArrayList) {
            if (element == null || JSONLinkedObject.NULL.equals(element)) {
                results.add(null);
            } else if (element instanceof JSONArray) {
                results.add(((JSONArray) element).toList());
            } else if (element instanceof JSONLinkedObject) {
                results.add(((JSONLinkedObject) element).toMap());
            } else {
                results.add(element);
            }
        }
        return results;
    }

    /**
     * Check if JSONArray is empty.
     *
     * @return true if JSONArray is empty, otherwise false.
     */
    public boolean isEmpty() {
        return myArrayList.isEmpty();
    }

}
